Feed mechanism for cartridge belts



G. T. BIXBY FEED MECHNISM FOR CARTRIDGE BELTS Filed May `23 4/ Ui v ,45' i.

Patented Nov. 13, 1945 2,388,670 AFEED MECHANISM FOR CARTRIDGE BELTS .Guy T. Bixby, Dayton, Ohio Application May 22, 1942, SerialNo. 444,058

(Cl. 89-33)u (Granted under the act of March 3, 1883, as amended April 30, 1928; 370 0. G. 757) 7 Claims.

The invention described -herein may be manufactured and used by or for the Government for governmental purposes, withoutl the payment to me of any royalty thereon.

This invention relates to cartridge belt feed mechanisms actuated by the firing oscillations (i. e'. by the recoil and counterrecoil) of automatic weapons.

It is an object of the invention to provide a compact structure directly securable to the gun attachments of presently existing nonactuated belt feeding mechanisms.

Another object of the invention is to effect complete feeding spool elimination th'rough the introduction of a pawl mechanism adapted to directly contact and drive forward any ammunition belt guided directly thereabove.

The invention makes available a structure so simple in basic operation asto require a minimum of changes to make it readily adaptable to both right and left hand feeds.

It also provides a mechanical arrangement in which all part movements due to cam actuation phantom outline 6 (i. e., the last named part re- (i. e. due to gun recoil) merely place the pawl mechanism in a position awaiting belt movement.

As a result of the above arrangement, the line feeding adjustment normally incident to direct ratchet drives is eliminated, cam compressed coil springs being used to effect actual cartridge belt advancement upon gun counterrecoil.

With the foregoing and other objects in view, the invention resides in the novel arrangement and combinations of parts and in the details of construction hereinafter described and claimed, it being understood that changes in the precise embodiment of the invention herein disclosed may be made within the scope of what is claimed Without `departure from the spirit of the invention A practical embodiment of the invention is illustrated in the accompanying drawing, Wherein:

Figure l is a side elevation of the improved feeding mechanism, with one caliber .50 round and associated weapon parts shown in ph'antom outline;

Figure 2 is a sectional view taken on the line 2-2 of Figure 1, with caliber .50 rounds and associated weapon parts shown in phantom outline;

vExcept for pawl parts repositioning, due to Weapon recoil, the showing of Figure 3 is similar to that of Figure 2;

Figure 4 is an enlarged end view of the cartridge finger stop or ratchet, and

mains entirely stationary during weapon firing) The forward end of the rod sh'own in outline E is fixed to a gun adapter located forward (i. e., to the left) of the part showing of Figure-1.

The booster I consists of a support 'I made up of a longitudinally disposed back plate 8 to which is welded or otherwise suitably attached a front cartridge belt guide plate II, a rear cartridge belt guide plate I2, and a centrally disposed pawl mounting bracket I3; a pawl mechanism I4 consisting of a driven lever I5, a yoke shaped driving lever I6, a pivot pin Il, a spring I8 and a contacting finger assembly I9; a pawl mechanism sh'aft 20; and two coil springs 2|. In Figure l of the drawing, it will be noted that the front (i. e., left hand) end of the back plate 8 slopes downwardly and forwardly to provide a mounting hole 9 for a pilot I0. The pilot Ill nts snugly in a pilot hole provided in the gun of outline 2, thereby furnishing the booster I additional support against twisting under firing shock.

As sh'own in Figures 2 and 3 of the drawing, the outer (i. e., left hand) portions of the front and rear cartridge belt guide plates II and I2 are sector shaped, with the longitudinal center line of the pawl mechanism shaft 2D passing directly through the apexes thereof. This arrangement permits ammunition belt pickup from below. Horizontal feeding of the ammunition belt can be equally well provided for by minor rearrangement of the pawl mechanism I 4 with respect to a horizontally disposed top surface for the cartridge belt guide plates. The upper in ner corner of each of the aforesaid guide plates is provided with a hole 22 through which the presently existing retaining pin of outline 4 passes. The last named pin also constitutes the supporting axle of the belt holding pawl shown in phantom outline 23, a later described element forming an essential part of the gun feedway shown in phantom outline 24. If desired, the upper and end surfaces of the gun feedway of outline 24 can be extended outwardly and slightly downwardly through installation of the cartridge belt cover shown in phantom outline 25. The cam contactor consists of a mounting plate VY26 secured to the outerV (i. e., left hand in ment with the rear (i. e., righthand) .faeefofithe driven lever I 5.

The numerous novel structural featuresiof three sub-assemblies compris-ingitheavvlfmehanism I4 are separately dealt with immediately below. Maximum forward or clockwise posit-icm ing of the driven lever I5 is centrolledfbyeaistop lug on said lever contacting 'withitheinclined upper .edge of the bracket I3, best shown inliigure 1 of the drawing, 'Periodic 'rearwardor coimterclockwise actuation of the driving leveriI-'from `.the .semi-upright Cunfired g gun) position 'of "Fig- .ure 1.2 'to' thepronounced `"outwardly `canted ffired gun) lposition OfFigure.3ds-accomplished bythe vinchlporatiori. of ahelical cam'3 I at the lever'zbase. 'A readilylmderstandable"sideprofile of :the helical cam .31., is shownin Figure '1.V AReturn of the driven iev-.er '1.5 'from .the '.(iired gun) positioning o'fEfigureS to 'the (unfiredgun) v.positioning .of Figure 251s accomplished .byiuserting vthe 011twardly turned :ends ".32 of .the .coil .springs "321 throughilongitudinal i disposed anchorholes'provided in .the frontend t rear cartrdgebelt .guide plates vil arid '.112 '.(a'diacent toitheiaxle .supplt- Ying 'lholes th.erethroug'h1.,,"Jqy L inserting the -pawl ,mechanismaxle 20,. and by,lastlyifpositionngithe Ahookedupper endsy 33 .of'fthe` coil .springs .22| -.within .therecesses provided atthe. ends-f ,thehnge 4pin 1.2.1,' whichnal parts gpositionngisclearly. i1-

.lustrated LiniFigure 1. In .closing, .as viewed .in

Eigureslz and .3,.it will be notedthatthedipper inner ,ejdge ofthe Ldriven leverzl' is :flat asindicated at I5 and isconstantly engaged' by .the fiat lower portion] 6 of the yoke ,shaped `driving lever Itunderthe'inuence of spring I.,8I,'Figs.` 1 and.

As 'viewed 'in 'Figure 1, of 'the drawing, kthe Agap Ybetween'the innersurfaces of 'the yoked ends of thedriving 'lever' IGi-ssufciently in excess of lthe longitudinalv width ofthe driven lever I5 torprovide ample Nroom for additional L installation, `upon the hinge pin 'I1,jo'f Athe-'spring I8 Vvv(the lower end of A`which -is jl'ieoked around the under 'surface o'f the I-stop lug 330,1Figurei5, Aand. the-upper end of Awhich passestbeneathandfslightly'beyond the lowermost of -ftheltwo slightly' in-t-urned faces of thefbase .portion of fthe yoke-shaped fdri-ving lever ll, f-as seen `-in Figure 5') n IPresence Aof j*the throw-up Vspring :I8 normally 'maintains ''the lengthwise axis-of 'the-'driving lever 'I 6 -in 41,l'-ie'-ref erenceline .positioning 'JOC indicated in"Figures '2 and;3 fof fthe drawing. fCloekwise vdeviation*from normal :lever I'Bpositioningis delatzwithi'below. As 'viewed .in fFigure "1, :the forward .(i. e., 'left hand) -.-armo f..the:drivinglever VIii is drillednd tappedzto provide 'f for .the installation of faanged spring: pawl13j4, a. screw 35, :and va",lockwa-sher l136. The @spring 34, .in l:conjunction with zthree ",stop pins ilater y.described in connection with the :enlarged view zof ;fligure 4, yconstitute what is :commonly referred to :as la. ratchet (i. ae., fthe 'spring pawl -34 g,performs-.the.;function :cf'iaicommon 1 pawl While the front ffiriger disk -.described;i`mmedi ately fbelow, in combination with :the above referred to stop pins, performs the function of a common ratchet wheel) Y As shown in Figures 1 through 4 of the drawing, the contacter finger assembly I9 consists of a front finger disk 31 provided with a rearwardly projecting spacer collar 38, and a rear finger disk 39 provided with a forwardly projecting Vspacer rod 4D and a still more forwardly project- :ing :axle 4%I r4tire., the .lastname'd passes through both thedfrivingfrod base Hportion andthe front finger disk 31). The disks 31 and 39 are retained proper fixed interrelationship by means of a pin -1--42 Vpassed .thrcughia hole provided in the spacer collar 38. The front finger disk 31 is com- Iposed of two (rather blunt) fingers 431 and 432, toi-ned bym-.common arcuate side 441, and of additionalnger 433, joined to the ringer 431 by a 'common arcuate side 442 and to the nger 432 byacommonfarcuate side 443. As viewed in the fienlargementfiofkll'igure 4, the counterclockwise tip .of each vof the aforesaid..ngersiiswlongitudinallyidrilled to receive three... rearwardly .proj ecting 'and iixedstop, Pins '45%, 45%,' .and .453.; which, 'in combination withthe IrQnt-'ngei'ldiskfl ,.ifOrm .in .efecta common ratchet wheel. .The irearinfger .disk 39 "duplicates thethreangeriarrangement 'of 'the front diriger :.disk! '3.1. .with .the single exceptionthatthe common arcuatesdes .ofthe former are longer and deeper than .thosefzthe llatter ';(i.e` the "front ASidesJdup'licatefblillet. con- :tourfwhi'le Vthe "rear ,sides .duplicate .cartridge casingfcontour "In order .to'loetter .describe-.the operation of .my inventiomllhave.additionally illustrated "(111 Figures .and `Z3) V.an.upwiairil-li' inwardly .fed Acartridge belt ,415 hy means .ofthe sixrounds'showniingphantom outlne-4'11 through Prior loperation deseription,.it..shou1d.bemoted that :positioning .of the .ammunition heit 324B is fideriticailjor 'both 'Fig-lues `2-and3. .It should-.also be'noted'thatFigures 1 andZIQpIeSenti-anunred gunrpositioning ofparts, whileFigureLB .represents a refdgunjpositioning .ofparts iii. e., inthe latter, ljthepawl:mechanismlll is represented' in its most loutwardly or. ;counterelockwisel positioning, poised 'forniovement ofthe `round o`f y,present outline `414 intothepositiouing of'thexrcunii cipres- 'ent 'outline i415) It^`shoul`c1 be-.S'till .'furfthennoted that :forea'ch inward ""stroke .of thepawl mechanism VlI4, around occupying the ,presentlligure 3 positioningio'f outline "415 will jfirs't Zdepressdown andspass'oven` then'beA lockedagainst outward es- `capage Vby,fthe belt holding 'pawl .of outline "213. Returning-toiFigure `-'1, it will -be'noted"that under unredJgumccnditions, the*visible "portion of the helical cam 13| projects Lincreasingly outwardly, from 1rightto1eft,vfdirectiy in the path of "the mostinwardly'disposedyportion--ofthecontacting surfaceiof the @longitudinally -xed roller bearing 28. It therefore follows that right hand movement of fthe gun o'f outline '12, togetherwith its attached booster mechanism I I4(as'a 'result of round firing), results in constantly increasing A,outwardly :movementfof fthe fpawl lmechanism I4 Imtil tithe y extreme .positioning `-olf *Figure 3 v`is fac- `compl-ished.l l I During the pawl mechanism repositioning-referred l to in fthe precedingl paragraph, Vtwo lclosel-y interrelated parts :movements occur. Firstly, ther'front and 4`rear iinger disks 31 `and 39 A*slidingly nfroll riaround, .irespectively fadacen-t bullet and :cartridge :casing surfaces :of 4.the frourid -f outline 414 (i. e., if a referencelineOAbeused to :indicate g; initial .position-ingrof the jfront v nger disk 31. of Figure :2, ...the :arcuate *side 5442 slides around its adjacent bullet surface in a clockwise direction until the aforesaid disk reaches a final positioning indicated by a second reference line OB in both Figures 2 and 3). Secondly, during the entire period of the above described movement of the front and rear nger disks 31 and 3S, the yoked driving lever Is of Figures 2 and 3 is continuously executing a jack knife movement with respect to the driven lever I5 (i. e., if the levers I3 and I5 of the pawl mechanism I4 be compared, respectively, to the blade and handle of a common jack knife, starting from the initial full open position represented by the reference line OC, the blade, I6 continues to "close up 'to the maximum closed positioning represented by a second reference line OD, after which it simply reverses the aforesaid movement by returning to the full open position of reference line OC). At this point, it should be especially noted that in passing from the front finger disk positioning of Figure 2 (i. e., from a positioning in which the contacting finger assembly I9 is in advance of the round of outline 414) to the same positioning of Figure 3 (i. e., to a positioning in which the contacting finger assembly I9 is immediately behind the round of outline 414). the engaging tip of the leaf spring 34 has shifted from an original position behind the driven face of the stop pin 453 to a new positioning behind the driven face of the stop pin 452. Therefore, with return of the gun of outline 2 to the longitudinal positioning of Figure 1 (i. e., upon complete removal of the cam restraint of Figure 3), the coil springs 2I will immediately force the pawl mechanism I4 back into the unfired gun positioning of Figure 2, thereby repositioning the round of present outline 414 into the positioning of the round of present outline 415. In accomplishing the above described round movement, it is also worthy of note that the "thrust exerted by the driving arcuate surfaces of the front and rear finger disks 31 and 39 is resolved substantially along the centerline of the ammunition belt 46.

Although the descriptions of this specification are specic to the illustrations of Figures 1 through 4, or readily understood modifications thereof, it is to be understood that there can be departures therefrom which still clearly fall within the iield and scope of the subject invention, and I therefore do not wish to be restricted thereto, but only insofar as the appended claims are so limited.

Having thus described my invention, what I claim as new and desire to secure by Letters Patent of the United States is:

1. A cartridge belt feed mechanism for automatic guns, comprising spaced plates adapted to be carried by a recoiling portion of the gun and normal to the center line thereof, a shaft mounted in said plates, an operating lever rockably mounted at one end on said shaft, and an arm pivotally mounted on the other end of said lever, an axle adjacent the lever and rotatably carried by said arm, cartridge feed discs mounted on the axle, a stop carried by the arm and engaging the lever to limit the movement of the arm relative to the lever, yielding means for keeping the stop in engagement with the lever, a cam carried by the lever, means adapted to be xed in the path of movement of said cam for engagement with the cam on the recoil of the gun portion to actuate said lever to position said discs for advancing a cartridge, means carried by the arm and means carried by a cartridge feed disc cooperating to advance a cartridge when the lever is moved toward the gun on counterrecoil, and means for actuating the lever upon said counterrecoil to feed a cartridge.

2. In a cartridge belt feed mechanism for automatic guns, a pivoted operating lever, cartridge advancing means carried by the lever and comprising anarm pivoted to said lever, an axle rotatably mounted in said arm, discs rotatably carried by said axle and having cartridge engaging l portions, laterally extending pins on one of said discs, a spring pawl carried by said arm ratcheting over said pins in one direction of the movement of the lever, and engaging said pins in the other direction to prevent retrograde movement of said discs.

3. A cartridge belt feed mechanism for automatic guns comprising spaced plates adapted to be carried by the gun, a shaft mounted in said plates, an operating lever rockably mounted on the shaft, a yoke-shaped member having arms pivotally connected with the operating lever, the pivot between said lever and arms having extensions beyond the arms, anchored spiral springs surrounding the shaft, the free end of the springs engaging said pivot extensions and urging the lever toward the gun, means for limiting the movement of the lever in such direction, an axle carried by said yoke-shaped member and having cartridge engaging and advancing discs rotatably mounted thereon, means carried by the yokeshaped member for engagement with the operating lever to limit the relative movement between said lever and said member, spring means for normally urging the yoke shaped member away from the gun, means carried by the yokeshaped member cooperating with the cartridge engaging and advancing discs to prevent retrograde movement of said discs, a cam on the operating lever, and a xed member cooperating with the cam to rock the lever away from the gun upon the recoil thereof.

4. A cartridge feed mechanism for automatic guns, comprising spaced plates adapted to be carried by the gun and normal to the center line thereof, a shaft mounted in the plates, an operating lever rockably mounted at one end on said shaft, and movable toward and from the gun, an arm pivotally mounted on the other end of the lever, an axle adjacent the upper end of said lever and rotatably carried by said arm, cartridge feed means mounted on the axle for advancing a cartridge upon the movement of the lever toward the gun, a cam carried by the operating lever and adapted to be engaged by means carried by the gun upon recoil of the gun to actuate said lever to position said cartridge means for advancing the cartridge, and spring means for actuating said lever upon the counterrecoil of the gun to feed a cartridge.

5. In a cartridge feed mechanism for automatic guns, a pivoted operating lever movable to and from the gun, oppositely disposed cartridge advancing discs rotatably carried by the lever and formed with a plurality of depressed arcuate portions in their peripheries arranged to successively engage and partially embrace the cartridge in feeding the same, positive means for moving the lever in one direction to position said discs for advancing a cartridge, and spring means for moving said lever in the other direction to advance the cartridge.

6. The invention of claim 5 characterized in that the positive means for moving the lever comprises a helical cam on the lower end of said le- `wermdjacent:bhefpivotal pontfthereoffandza xed :memberconstructed-l-andarrangedto ',coact with `said :cam fno V'move ysaid lever, :and the yspring means comprises a coi1spring"having operative -connection *with the yupper v`end sof: saiddever.

'-7. :Inza cartridge ,belt-,feed mechanism of;au ,tomatic guns, a :pivoted :operating leverrmovable to and fromithe gun, a. member pivotally mount- .fedonrtheupper endof saidfmemben a-horizontal '.extendingzaxle -.carriedby said membenopposiie- "10 ily disposed :cartridge :advancing adiscs rotatably carried :by :said axle :and 1 provided :with 1a i plural- Eity of equa'liyispaced depressed :arcuate Aportions in ftheir;peripheriesarranged1 to :successively en- -gage and .partially embrace :the z cartridge kto be ,fedgpositive means forfmoving :theilever in one directon :to .position .said discs forradvancing a car- 'ridgne,amispring meansv for-moving. said lever in the other direction .to advanceathe'cartridge.

GUY 'I. "BIXBY, 

